I us my Mark III mainly for portraits but I'm going on a trip and want to take videos of my daughter. Will be using mostly nifty fifty and 30 mm IS USM for lenses. Could someone rundown what settings they would use for basic video? I read the manual and the choices make me dizzy. Just want basic memories of my kid, not an art film. Any help greatly appreciated.

Choose between Auto Exposure mode or Manual Exposure mode. Manual is better, but Auto is easier if you don't have much experience adjusting aperture, shutter speed, or ISO manually.

Choose your frame rate. If you're shooting in full 1080 definition, you can choose 24 or 30 frames per second. Everyone will argue on this, but the basic idea is 30 fps is more of a "video" look and 24 is more of a film, slightly strobing look. I like the look of 24, even for home movies. But try both and see for yourself.

Audio - test the levels and set it manually for each setting you find yourself in.

You do not need to change anything for basic video. The advanced settings are good when you get into a bit more advanced uses, or if you find that the default settings don't do the job., They work fine for most users.

Unless you've got a lot of motion, don't bother with ALL-I, use ALL-IPB. It'll save a lot of space on the card and give you pretty much the same quality. And the general rule is use a shutter speed that's 1/(2*fps). So if you're shooting at 24fps, set your shutter at 1/50, or for 30fps shoot 1/60. This is for a more film like look, see http://luispower2013.wordpress.com/2013/03/12/the-180-degree-rule/ for a decent basic intro to it.

And if you want decent audio, get an external hot-shoe mic. Doesn't have to be real expensive, even the basic $50 ones will be much superior to the built-in mono mic.

And it's generally recommend to use the Neutral Picture Style for video if you're not going to do any real color grading in post. Lots on this subject, but Neutral or maybe Standard will probably be OK for you.

Thank you! I'm guessing from what I read that I could just put it in auto and shoot without selecting anything but the default if I wanted? I was told it doesn't autofocus in video so I'm guessing that's all I'd have to do?

Thank you! I'm guessing from what I read that I could just put it in auto and shoot without selecting anything but the default if I wanted? I was told it doesn't autofocus in video so I'm guessing that's all I'd have to do?

This is true. It doesn't do autofocus, unless you own a t4i, t5i or 70D. But, thats a good thing!

Its like driving a stick versus auto... it gives you the power. So play around, there is also quick focus, where you press the shutter button prior to recording video and pow... its focused.

While recording, use manual focus, and pull the focus... its a video trick that makes it bit more film like.Sample focus pull: Quick and Dirty DSLR Focus Pull

The 5D3 will autofocus in video, both before and while rolling. However this is single-shot AF, not continuous AF and you must trigger this by pressing the AF-ON button. That single-shot AF can be either contrast detect or phase detect (quick mode, if not rolling).

If done while rolling video, a slight brightness glitch will be recorded, which you'll either have to accept or edit out.

For casual hand-held video, image stabilization is vital. I would strongly suggest you use a 24-105 f/4 or similar lens which gives IS plus a decent zoom range.

Also in bright conditions the aperture will stop down, so you lose the cinematic shallow depth of field. Maintaining a wide aperture *and* 1/60th shutter speed generally requires a variable ND filter for outdoors. However this is yet another manual item you'd have to control. For pro video work we always shoot fully manual (except sometimes auto ISO), check exposure using zebras and focus using color peaking on an EVF. However that's too much hassle for a vacation video.

You'll have the 5D3 with you, and likely you don't want to take a separate camcorder, and want something better than a cell phone video. Just using full auto will at least get some footage. Make sure you take extra batteries because they are consumed much faster in video mode.

As already stated the build-in mic is limited, even a less expensive hot shoe mic would be better. Using IPB (not All-I) at 1080p/30 or 1080p/25 is probably best. You will likely be displaying it on a 30 or 25 fps viewing device.

I suggest you shoot some test material in various conditions beforehand to get accustomed to how it works.